Polyamides of dialkyl dicarboxylates and 2,6-diaminopyridine, and quaternary salts thereof



Patented Mar. 2, 1954 i I UNITED. STATES PTENT oFFrcE POLYAMIDES OF DIALKYL DICARBOXYL- ATES AND 2,6-DIAMINOPYRIDINE, AND QUATERNARY SALTS THEREOF Thomas T. M. Laakso and Delbert D. Reynolds, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application February 12, 1952, Serial No. 271,286

13 Claims. (01. 260-78) This invention relates to resinous polyamides terials. They are also valuable as components of dialkyl dicarboxylates and 2,6-diaminopyriin imbibition printing blanks, where the process dine, to quaternary ammonium salts thereof, and involves dye transfer from a tanned gelatin re- :to the preparation of the same. lief to the gelatin-mordant composition coated 'Resinous compositions containing nitrogen 5 cellulose ester or synthetic resin sheet or film, heterocyclic nuclei are known to act as mordants paper, glass or similar support. Other colloids for acids, particularly in color processes wheresuch as polyviny1 alcohol or partially hydrolyzed in acid dyes are employed. However, the utility polyvinyl acetate can be employed in place of of many such known compositions as mordants gelatin. Also, other materials can be added to is quite lim t For ex mple, linear polyamides the composition of gelatin-dye-mordant such as prepared by condensing bis keta ketonic carsilver halide dispersed therein so that there is boxylic acid dialkyl esters such as, for example, obtained a material which functions both as a ethyl ester of acetone dicarboxylic acid, with a light-sensitive photographic element and as an 'diaminopyridine are known to be excellent dye imbibition blank. intermediates, and in photographic processes 15 It is, accordingly, an object of our invention to their alkali-metal salts have been shown to funcprovide a new class of polyamide resins and tlon as good color formers. However, they are quaternary salts thereof. Another object is to rel y poor mordanting agents and the presprovide polyamide resins and quaternary salts ence of an enolizable methylene group interferes thereof which are excellent mordants for acid ,with' their use in certain color processes where dyes in certain color processes. Another object a stable, powerful mordant is required for fixing is to provide methodsfor preparing the polyamide acid dyes. resins and quaternary salts of the invention.

We have now found that superior precipitants Other objects will become apparent hereinafter. and mordants for acid dyes, particularly suitable In accordance with the invention, we prepare for fixing acid dyes in photographic layers, are our new polyamide resins and quaternary salts obtained by condensing certain dialkyl dicarthereof by heating one or more dialkyl dicarxyl t whi h c nta n no en liz le m hy e boxylates selected from the group consisting of gro p, with 2,6d m n Dy i ine, under conditions esters having the general formula: which result in resinous, high molecular weight 0 polyamide products. We have found further that 1 II our new polyamide resins are readily convertible ROJEAOHDFCFOR to quaternary salts, and in this form function and .1 even better as mordanting agents. While the 0 basic polyamides of our invention are insoluble ll R in water, but soluble in some organic solvents such as methanol and in-dilute aqueous mineral and organic acids, the quaternary salts are in addition partially soluble in pure Water. The amount of acid used can be suflicient to just dissolve the resin, although higher concentrations thanthat can be employed, if desired. The new polyamides and'their quaternary salts readily form substantially water-insoluble salts with water-soluble acid dyes. They are also compatible with various colloidal materials such as gelatin. These properties, together with their 4 relatively large molecular dimensions make our wherein n represents a whole number from 2 tot and R represents an alkyl group containing from to 4 carbon atoms (as. methyl, ethyl, propyl, isopropyl, butyl, etc., groups), and 2,6-diamino- 4.0 pyridine, in the proportions of approximately-a mole of carboxylate compound to each mole of 2,6-diaminopyridine, at a temperature of from 175 to 250 C., until the condensation reaction is substantially complete, and isolating the polymeric product by extraction methods, Washing, etc., then converting the product to a quaternary salt new polyamides and quaternary salts thereof outby heating it t an eqtfivalent amount or more standing mordants for fixing soluble acid dyes Of an alkyl halide, a dialkyl sulfate or an alkyl such as those employed in photographic layers. WW- at agtentpemture P akfout 100 They are particularly Valuable as mordants in until the quaternization reaction is complete, preventing diffu l n of the dyes when incomeand then purifying the quaternary salt obtained, rated in the. form of their dilute acetic acid solufor examplerblf re extlfactlofi h flops inv light, filter in backing layers solvent such as dlfithyl ether and drying the prodsigned to prevent back reflection from the film uct.' No cycliaation was ob'servedtotake place support; etc., inlight-sensitive photographic maunder the conditions of the reaction. Suitable inopyridine, in the form of the free base the recurring structural unit of the formula:

I ll -(}(OH:)..CNH \N -NH- wherein n has the above defined meaning, and. containing in the case of the terephthalates reaction products with 2,6-diaminopyridine, in the form of the free base, the recurring structural unit of the formula:

and in the quaternized salt forms the recurring structural units of the formulas:

i n l C(CH:)flCNH-K NE- and o 0 H H H t 7H c C-N r.

wherein n has the previous definition and R1 represents an alkyl group containing from i to 4 carbon atoms (e. g. methyl, ethyl, n-propyl; n-butyl, isobutyl, etc. groups), but preferably primary alkyl groups of l to 4 carbon atoms, and X represents an arylsulfonic acid radical (i. e. and arylsulfonate anion containing from 6 to 7 carbon atoms) e. g. a benzenesulfonate anion, a p-toluenesulionate anion, eta, an alkylsulfuric acid radical (i. e. an alkylsulfate anion containing from 1 to 4 carbon atoms), e. g. methylsulfate, ethylsuliate, n-propylsulfate, n-butylsuliate, etc., and a halide anion e. g. chloride anion, bromide anion and an iodide anion, (anion). Suitable quaternizing agents include methyl benzensulfonate, ethyl benzenesulionate, propyl benzensulfonate, butyl benzenesulfonate, methyl p-toluenesulfonate, ethyl-p-toluenesulionate, propyl p toluenesulfonate, butyl p toluenesulfonate, etc., dimethyl sulfate, diethyl sulfate, dipropyl sulfate, dibutyl sulfate, etc.,

methyl bromide, ethyl bromide, propyl bromide, butyl bromide, etc., and the corresponding alkyl chlorides and iodides, and the like.

The following examples will serve to illustrate further our new class of polyamide polymers.

of oxalic acid under similar or other acid radical solid reaction product quaternary ammonium salts thereof, and the manner of their preparation.

Example 1 54.5 g. (0.5 mol) of 2,6-diaminopyridine and 101 g. (0.5 mol) of freshly distilled diethyl adipate were mixed together and heated under a nitrogen atmosphere for 5 days, at a temperature of approximately 200 C., in an electrically heated oil bath. The dark-brown viscous material obtained was poured while still molten into an enameled tray and allowed to cool. The brittle cake was broken up and extracted with acetone in a Soxhlet extraction apparatus until no further material dissolved. The residual light-tan powder was dried and analyzed. The results indicated that the product was a polyamide containing approximately equimolar amounts of the reactants.

The product was soluble in 1% aqueous hydrochloric acid.

Example 2 2 g. of the polyamide resin of Example 1 were heated for several days with 5 g. of methyl-ptoluenesulfonate at steam bath temperature. The

was separated and extracted several times with ether and dried. Analysis gave by weight 9.2% nitrogen and 7.6% sulfur compared with the calculated theoretical of 10.3% nitrogen and 7.9% sulfur. The product was not completely soluble in water, but formed clear solutions on addition of a small amount oi acetic acid. 1.

Example 3 54.5 g. (0.5 mol) of 2,6-diaminopyridine and 8'? g. (0.5 mol) of freshly distilled diethyl succinate were placed in a sealed tube under a. nitrogen atmosphere and heated for 5 days, at a tem perature of about 0., in an electrically heated oil bath. The dark-brown viscous material obtained was poured while molten into an enameled tray and allowed to cool. The brittle cake was broken up and. extracted with acetone until no further material dissolved therefrom. The residual dark powder was dried and analysisindicated that it was a linear polyamide containing approximately equimolar quantities of thereactants.

Calculated, Foiled; Analysis Percent Percent 5 56. 1 4. 7 5. l Nitrogen l6. 7 20. 7

The product was insoluble in water, but soluble in dilute aqueous hydrochloric acid.

Example 4 'the 5 day heating period; The product 1 cc 2- phthalate were heatedtogether in an electrically buff, colored powder molar proportions in I ants as indicated by the following results,

-:tha-t a high quality quaternary salt-oi the polyamide had been obtained.

Example 5 Equimolar quantities of 2,6-diaminopyridine and diethyl sebacate were heated together and the product purified following the procedure of Example 3, except that a Bunsen valve was used :to seal the tube. Also the reaction temperature was raised slowly from 180 C. to 210 C. during was found to be a linear polyamide containing approximate- 1y equimolar quantities of the reactants in the molecule.

The product was insoluble in water, but soluble in dilute aqueous hydrochloric acid.

Erample 6 A quaternized salt of the polyamide of Example 5 was prepared with methy1p-toluenesulfonate following the process described in the preceding quaternization examples. Analysis of the salt gave the following results:

- Calculated, Found Analysls Percent Percent The quaternized salt was partially soluble in water, but completely soluble in dilute aqueous acetic acid, hydrochloric acid, etc.

Example 7 (0.3 mol) of 2,6-diaminopyridine and mol) of freshly distilled diethyl tereheated oil bath, at 210 220" 0., for a period or 4-8 hours, in a flask sealed with a Bunsen valve. The solid reaction product was extracted with acetone in a Soxhlet extraction apparatus-until "no further material dissolved. .The residual lightwas dried and analyzed.

The results indicated thatthe product was a linear polyamide containing approximately equithe moleculeof the react- Calculated Found,

Analysls Percent Percent 0arbon 65. 2 64. 3 Hydrogen 3. 7 4. Nitrogen 17. 5 16.3

water, but soluble tities of 2,6-diaminopyridine and dimethylphthalbe substituted therefor to give "wherein"n-represents a whole number'of from 2 6 ate were reacted under similar conditions, -;no resinous polyamide was obtained, but only a crystalline product, apparently a diphthalimide corresponding to the following structural formula:

This product would not quaternize with either methyl-p-toluenesu1fonate 0r n-butyl methanesulfonate.

Example 8 I r 5 g. of the polyamide resin produced according to Example 7 were heated with 20.9 g. of methylp-toluenesulfonate on a steam bath for 48 hours.

The product was analyzed after repeatedextractions with ether and thorough drying. The quaternized product was found to contain by weight 59.3% carbon and 10.9% nitrogen compared with calculated theory of 59.2% carbon and 9.8% nitrogen.

Although the preceding quaternizing examples show the quaternization of the polyamides of our invention with only methyl-p-toluenesulfonate, it will be understood that equivalent amounts of the other mentioned quaternizing reagents can the corresponding quaternary ammonium salts, which are equally useful as mordanting agents in various color processes. The quaternization reaction can also be carried out in the presence of an inert diluent such as, for example, methanol, ethanol, dioxane, etc., the resulting salt being isolated and purified by the usual methods employed in such processes.

What we claim is: 1; An alkyl quaternary salt of a resinous polymer selected from the group consisting of an i and an alkyl quaternary salt of a linear polyamide consisting of recurring structural units of the formula: #O \N to 8, R1 represents an alkyl group containing from 1 to 4 carbon atoms and X represents an anion selected from the group consisting of arylsulfonate anions containing from 6 to 7 carbon atoms, alkylsulfate anions containing from 1 to 4 carbon atoms, a chloride anion, a bromide anion and an iodide anion.

2. An alkyl quaternary salt of a resinous, linear polyamide consisting of recurring structural units of the formula:

wherein n represents a whole mnnber of from .2

to 8, R1 represents an alkyl group containing from 1 to 4 carbon atoms and X represents an srylsulfonate anion containing from 6 to 7 carbon atoms.

3. An alkyl quaternary salt of a resinous, lineor polyamide consisting of recurring structural units oi the formula:

0 ALGA-NH wherein R1 represents an alkyl group containing from 1 to 4 carbon atoms and X represents an arylsulfonate anion containing from 6 to 7 carbon atoms.

4. An alkyl quaternary salt of a re inous, linear polyamide consisting of recurring structural units of the formula:

5. An alkyl quaternary salt of a resinous, linear polyamide consisting of recurring structural units or the formula:

6. An alirvl quaternary salt of a resinous, lineor polyauude consisting of recurring structural units of the formula:

7. An alkyl quaternary salt of a resinous, linear polyamide consisting of recurring structural .units of the formula:

8. A resinous polymer selected from the group consisting ofa linear polyamideconsisting of recurring structural units of the formula:

iii)

8 and a. linear polyamide consisting of structural units of the tormula:

wherein n represents a whole number or from 9. A resinous, linear polyamide consisting of recurring structural units of the formula:

wherein n represents a whole number oi 1mm "2 to 8. i

10. A resinous, linear polyamide consisting of recurring structural units of the formula:

11. A resinous, linear polyamide consisting of recurring structural units of the formula:

12. A resinous, linear polyamide consisting of recurring structural units or the formula:

'13. A resinous, linear polyamide consisting of recurring structural units of the formula:

THOMAS T. M. LAAKSO. DELBERT D. REYNOLDS.

References Cited in the file of this patent UNITED STATES PATENTS and Printing, V01. II, Reinhold, 1951, 52 and 336 to 338. 

1. AN ALKYL QUANTERNARY SALT OF A RESINOUS POLYMER SELECTED FROM THE GROUP CONSISTING OF AN ALKYL QUANTERNARY SALT OF A LINEAR POLYAMIDE CONSISTING OF RECURRING STRUCTURAL UNITS OF THE FORMULA: 